This invention relates to aerosol antiperspirant compositions, and compositions for making them. More particularly, it relates to compositions having high efficacy and improved suspension stability.
Compositions designed to stop or reduce the flow of human perspiration are well known in the cosmetic and chemical literature. Antiperspirants typically contain an astringent material, such as an astringent aluminum or zirconium salt. The compositions are designed to deliver the active to the skin in an effective form; while being cosmetically acceptable.
Many antiperspirant compositions contain the antiperspirant active material in particulate form, suspended in an anhydrous liquid. These compositions are typicaly applied to the skin as sprays (both aerosols an non-pressurized pump sprays) and roll-ons. Many liquid formulations are described in S. Plechner, "Antiperspirants and Deodorants" 2 Cosmetics, Science and Technology 373-416 (M. Balsam and E. Sagarin, editors, 1972). Such compositions are also described, for example, in British Patent Specification No. 1,341,618, published Dec. 28, 1973; British Patent Specification No. 1,341,618, published Dec. 28, 1973; British Patent Specification No. 1,341,748, published Dec. 28, 1973; U.S. Pat. No. 4,278,655, Elmi, issued July 14, 1981; and European Patent Specification No. 28,853, Beckmeyer et. al., published June 20, 1981.
Antiperspirant compositions have also been described in the literature containing active materials with improved efficacy. These preferred actives have a selected distribution of polymeric aluminum metal species (containing aluminum with and without zirconium), resulting in improved antiperspirant efficacy. Such actives, and compositions containing them, are described, for example, in U.K. Patent application No. 2,048,229. Fitzgerald et al, published Dec. 10, 1980; U.S. Pat. No. 4,359,456, Gosling et al., issued Nov. 16, 1982; U.K patent application No. 2,144,992, Calalghan et al., published Mar. 20, 1985; European Patent Publication No. 183,171, Murray et al., published June 4, 1986; and European Patent Publcation No. 191,628, Inward et al., published Aug. 20, 1986.
It has been found that aerosal antiperspirant, containing preferred actives with suspension agents typically used in the art, may be subject to clogging. It has also been found that this clogging is particularly acute with preferred, high efficacy actives having selected polymeric distribution. Therefore, such compositions may be difficult or impossible to dispense from conventional aerosol containers.
It has now been found that the compositions of the present invention contain highly efficacious antiperspirant actives, with selected polymeric distribution, selected hydrophobically-treated clays and specific levels of activator (based on the clay levels) avoid this problem. Compositions of this invention also provide improved redispersibility (i.e., the ability to resuspend the antiperspirant active after settling.)
All percentages and ratios herein are by weight unless otherwise specified. Additionally all measurements are made at 25.degree. C. unless otherwise specified.